Narrative:

2 mi off the runway final approach. We were on the final segment of a 9 hour 12 min flight time day. Approach control asked if we had the airport and were then cleared for a visual approach to runway 19R. The ATIS reported visibility of 8 mi, scattered clouds with a fog bank to the west. After turning base, contacted tower and given clearance to land. At approximately 600 ft MSL and 2 mi to landing, the tower controller reported in the blind the new ATIS advising the field was now IFR with visibility 1 mi in fog. With the aircraft in landing position and the runway clearly in sight I elected to land. I do not know if in retrospect it was legal to do so on a visual approach when the WX changes to less than visual minimums and you are on the final approach segment.

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Original NASA ASRS Text

Title: AN MD80 FLC ON SHORT FINAL RECEIVED AN ADVISORY THAT SNA WAS NOW IFR AND CONTINUED TO A VISUAL LNDG.

Narrative: 2 MI OFF THE RWY FINAL APCH. WE WERE ON THE FINAL SEGMENT OF A 9 HR 12 MIN FLT TIME DAY. APCH CTL ASKED IF WE HAD THE ARPT AND WERE THEN CLRED FOR A VISUAL APCH TO RWY 19R. THE ATIS RPTED VISIBILITY OF 8 MI, SCATTERED CLOUDS WITH A FOG BANK TO THE W. AFTER TURNING BASE, CONTACTED TWR AND GIVEN CLRNC TO LAND. AT APPROX 600 FT MSL AND 2 MI TO LNDG, THE TWR CTLR RPTED IN THE BLIND THE NEW ATIS ADVISING THE FIELD WAS NOW IFR WITH VISIBILITY 1 MI IN FOG. WITH THE ACFT IN LNDG POS AND THE RWY CLRLY IN SIGHT I ELECTED TO LAND. I DO NOT KNOW IF IN RETROSPECT IT WAS LEGAL TO DO SO ON A VISUAL APCH WHEN THE WX CHANGES TO LESS THAN VISUAL MINIMUMS AND YOU ARE ON THE FINAL APCH SEGMENT.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.